1ambda 0589e27e7b [ZEPPELIN-2008] Introduce Spell ... ### What is this PR for? Implemented **Spell** as one of Helium categories. *Technically, it's the frontend interpreter* runs on browser not backend. Spell can provide many benefits. 1. Anyone can install, remove easily using helium package registry by #1936 2. Implementing spell is extremely easier rather than adding backend interpreter 3. Can use existing javsacript libraries. (e.g [flowchart.js](http://flowchart.js.org/), [sequence diagram js](https://github.com/bramp/js-sequence-diagrams), ...). This enable us to add many visualization tools. Imagine that you can implement some custom interpreters with few lines of code like [flowchart-spell-example](https://github.com/apache/zeppelin/compare/master...1ambda:ZEPPELIN-2008/introduce-spell?expand=1#diff-364845b20d68e4d94688e44fef03da98) 4. The most important thing is, spell is not only interpreter but also display system. Because it runs on browser. So we can use spell display system with another spell **Display System with Spell** (see the screenshot section below) **In future**, we will be able to combine existing backend interpreters with spell like (**not supported in this PR cause we need to modify backend code a lot**) ``` // if we have markdown spell, we can use `%markdown` display in the spark interpreter %spark val calculated = doSomething() println(s"%markdown _${calculated}) ``` I added some examples. Checkout `echo`, `markdown`, `translator`, `flowchart` spells. ### What type of PR is it? [Feature] ### Todos * [x] - Add `SPELL` as one of Helium categories. * [x] - Implement framework code (`zeppelin-spell`) * [x] - Make some examples (flowchart, google translator, markdown, echo) * [x] - Support custom display system * [x] - Fix some bugs in `HeliumBundleFactory` * [x] - Save spell rendering result into `note.json` while broadcasting to other websocket clients * [x] - Fix `renderText` for stream output ### What is the Jira issue? [ZEPPELIN-2008](https://issues.apache.org/jira/browse/ZEPPELIN-2008) ### How should this be tested? - Build `mvn clean package -Phelium-dev -Pexamples -DskipTests;` - Go to helium page `http://localhost:8080/#/helium` - Enable all spells - Go to a notebook and refresh - Follow actions in the screenshots below. ### Screenshots (if appropriate) #### Flowchart Spell (Sample)  #### Google Translator Spell (Sample)  #### Display System with Spell  ### Questions: * Does the licenses files need update - NO * Is there breaking changes for older versions? - NO * Does this needs documentation? - YES, but framework can be enhanced so i would like to defer to write document right now. Author: 1ambda <1amb4a@gmail.com> Closes #1940 from 1ambda/ZEPPELIN-2008/introduce-spell and squashes the following commits: c1b5356 [1ambda] fix: RAT issues e07ecd3 [1ambda] fix: Set width for spell usage 6c91892 [1ambda] feat: Display magic, usage for spell 5be2890 [1ambda] feat: Support spell info 822a1d8 [1ambda] style: Remove useless func wrap for helium 35d0fcc [1ambda] fix: Update desc for spell examples 49e03fc [1ambda] fix: List visualziation bundles only in order 4029c02 [1ambda] fix: ParagraphIT, parameterizedQueryForm 08eba10 [1ambda] refactor: renderGraph in result.controller.js 69ce880 [1ambda] fix: Resolve append (stream) output 0f2d8b6 [1ambda] fix: Resolve output issue fc4389e [1ambda] fix: Resolve RAT issues c8c8f0e [1ambda] fix: Add setErrorMessage method to Job 4fec44c [1ambda] refactor: NotebookServer.java 1227d7d [1ambda] refactor: result controller retry 9fb7438 [1ambda] feat: Save spell result and propagate 3cdf2da [1ambda] fix: NPM installation error 72aadbf [1ambda] feat: Enhance translator spell bd2b3ef [1ambda] style: Rename generator -> data cac0667 [1ambda] style: Rename to Spell e81cb03 [1ambda] example: Add echo, markdown 0fa7eda [1ambda] feat: Support custom display c906da6 [1ambda] feat: Update examples to use single FrontIntpRes 5c49e6e [1ambda] feat: Automated display type checking in result 5810bf1 [1ambda] feat: Apply frontend interpreter to paragraph a163044 [1ambda] feat: Add flowchart, translator examples 247d00f [1ambda] feat: Add frontend interpreter framework e925967 [1ambda] feat: Support FRONTEND_INTERPRETER type in frontend c02d00a [1ambda] feat: Support FRONTEND_INTERPRETER type in backend		2017-02-02 08:33:48 +09:00
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index.js	[ZEPPELIN-2008] Introduce Spell	2017-02-02 08:33:48 +09:00
package.json	[ZEPPELIN-2008] Introduce Spell	2017-02-02 08:33:48 +09:00
pom.xml	[ZEPPELIN-2008] Introduce Spell	2017-02-02 08:33:48 +09:00
zeppelin-example-spell-markdown.json	[ZEPPELIN-2008] Introduce Spell	2017-02-02 08:33:48 +09:00